Li S M, Wang Y A, Liu W, Wu Z Y, Chen L, Cai X L, Zhang R, Yang W J, Liu Y, Ma Y M, Gong S Q, Zhang S M, Ren Q, Han X Y, Ji L N
Departments of Endocrinology and Metabolism, Peking University People's Hospital, Peking University Diabetes Center, Beijing 100044, China.
Zhonghua Nei Ke Za Zhi. 2021 May 1;60(5):438-445. doi: 10.3760/cma.j.cn112138-20200515-00483.
To explore the associations of urinary retinol binding protein (RBP) and β-microglobulin (β-MG) with urinary albumin to creatinine ratio (UACR) and renal function in hospitalized patients with type 2 diabetes mellitus (T2DM). A total of 1 030 Chinese patients with T2DM were included in this study. The subjects were divided into the UACR normal group (<30 mg/g), microalbuminuria group (30-300 mg/g) and macroalbuminuria group (>300 mg/g). Patients with normal UACR were further divided into two groups according to the estimated glomerular filtration rate (eGFR): the eGFR low group (<90 ml·min·1.73m) and the normal eGFR group (≥90 ml·min·1.73m). Urine RBP and β-MG levels among the groups were compared. Multiple linear regression analyses were applied to evaluate risk factors of urine RBP and β-MG. In all patients (=1 030), urine RBP and β-MG increased gradually with the increase of UACR across the three groups, the proportions of abnormal urine RBP (>0.7 mg/L) and β-MG (>370 μg/L) in these groups were 3.8%, 8.5%, 39.0% (<0.001), and 12.9%, 26.7%, 46.8% (<0.001), respectively. In the UACR normal group (=788), 12.2% of the patients were with eGFR<90 ml·min·1.73m. The proportion of abnormal β-MG (>370 μg/L) was higher in the eGFR low group than that in the eGFR normal group (29.2% vs. 10.7%, <0.001). Multivariate linear stepwise regression analyses were performed using natural logarithm of urine RBP or β-MG as dependent variable, and showed that urine RBP was independently associated with UACR (=0.0005, <0.001), serum creatinine (=0.006, <0.001) and glycosylated hemoglobin A1c (=0.050, =0.001), and β-MG was independently correlated with UACR (=0.000 4, <0.001), serum creatinine (=0.011, <0.001), systolic blood pressure (=0.005, =0.031) and fasting blood-glucose (=0.027, =0.046). Urine RBP and β-MG are positively associated with high UACR and impaired renal function in T2DM patients, and these changes could occur before UACR and eGFR turned out to be abnormal. It is recommended that urine RBP and β-MG be detected as early as possible to identify diabetic kidney disease in patients with normal UACR and eGFR.
探讨住院2型糖尿病（T2DM）患者尿视黄醇结合蛋白（RBP）和β-微球蛋白（β-MG）与尿白蛋白肌酐比值（UACR）及肾功能的关系。本研究共纳入1030例中国T2DM患者。将研究对象分为UACR正常组（<30 mg/g）、微量白蛋白尿组（30 - 300 mg/g）和大量白蛋白尿组（>300 mg/g）。UACR正常的患者根据估算肾小球滤过率（eGFR）进一步分为两组：eGFR低组（<90 ml·min·1.73m²）和eGFR正常组（≥90 ml·min·1.73m²）。比较各组尿RBP和β-MG水平。采用多元线性回归分析评估尿RBP和β-MG的危险因素。在所有患者（n = 1030）中，三组患者尿RBP和β-MG均随UACR升高而逐渐升高，三组中尿RBP异常（>0.7 mg/L）和β-MG异常（>370 μg/L）的比例分别为3.8%、8.5%、39.0%（P<0.001），以及12.9%、26.7%、46.8%（P<0.001）。在UACR正常组（n = 788）中，12.2%的患者eGFR<90 ml·min·1.73m²。eGFR低组β-MG异常（>370 μg/L）的比例高于eGFR正常组（29.2%对10.7%，P<0.001）。以尿RBP或β-MG的自然对数为因变量进行多元线性逐步回归分析，结果显示尿RBP与UACR（β = 0.0005，P<0.001）、血清肌酐（β = 0.006，P<0.001）和糖化血红蛋白A1c（β = 0.050，P = 0.001）独立相关，β-MG与UACR（β = 0.0004，P<0.001）、血清肌酐（β = 0.011，P<0.001）、收缩压（β = 0.005，P = 0.031）和空腹血糖（β = 0.027，P = 0.046）独立相关。尿RBP和β-MG与T2DM患者高UACR及肾功能损害呈正相关，且这些变化可能在UACR和eGFR出现异常之前就已发生。建议尽早检测尿RBP和β-MG，以识别UACR和eGFR正常的患者中的糖尿病肾病。
